696 CARREL— TRANSPLANTATION OF ORGANS. [November 6, 



days in cold storage. The femoral pulse remained normal. A few 

 months after the operation, the abdomen was reopened and the cir- 

 culation through the new artery found normal. There was no modi- 

 fication of its caliber. The animal remained in good health. Dur- 

 ing the years 1907 and 1908, no modification of the femoral pulse 

 occurred. It is still normal to-day, one year and a half after the 

 operation, and the animal is in excellent condition (Fig. 3). 



These experiments demonstrate that the clinical results of the 

 transplantation of preserved vessels can remain satisfactory for a 

 long time. However, in both cases, the operation was performed 

 under unfavorable circumstances. The grafted arteries belonged to 

 an animal of different species and the method of preservation used 

 in both cases was imperfect. The wall of these vessels underwent 

 certainly marked histological changes. Nevertheless they are still 

 able to perform normally their functions. 



Conclusions. 



The results of the experiments of preservation of arteries in cold 

 storage must be considered from both the anatomical and the prac- 

 tical standpoint. 



From an anatomical standpoint, they show that an artery from 

 an animal can be kept outside of the body for two days at least, 

 transplanted onto another animal of the same species, and live again 

 without presenting any change of its constituent elements. The 

 transplantation of vessels killed by drying, heating or fixation in 

 formalin is followed by degeneration of the wall and replacement 

 by connective tissue from the host. When the vessel is kept in cold 

 storage for a longer period of time, all the muscular fibers of the 

 media disappear a few days after transplantation. If the period 

 spent in cold storage is still longer, eight months for instance, throm- 

 bosis occurs. 



From a practical standpoint, these experiments demonstrate that 

 the preserved vessels, even if their muscular fibers are completely 

 resorbed, are an excellent substitute for arteries and perform nor- 

 mally their functions for months and years. 



